Defibrillation is a medical procedure for which the use was initially and legally reserved for physicians, either in a hospital environment or, using portable devices, on the site of the heart attack. It consists of applying by means of electrodes, to the chest of a patient suffering from “sudden death”, generally caused by ventricular fibrillation, electric pulses or shocks of controlled duration, shape and intensity so as to restart normal cardiac activity.
Numerous external cardiac defibrillator systems intended to be used outside the hospital environment, by non-professionals, are now known. The difficulty is that of preventing an electric shock being emitted while the patient's heart is not in a state of tachycardia or ventricular fibrillation. In this way, a defibrillator intended to be used by non-professionals should be designed to restrict shock activation to this scenario, even if requested by the user (referred to herein as the “rescuer”). For this, the device records signals detected by the electrodes positioned on the patient in order to automatically establish a diagnosis (generally in the form of a simplified electrocardiogram) and decide on the appropriateness of discharging the electric shock.
A distinction is made between so-called semi-automatic defibrillators, wherein the rescuer needs to activate electric shock administration manually after moving away from the patient so as to no longer touch the patient, and so-called automatic defibrillators, wherein the electric shocks are sent automatically after a voice message has prompted the rescuer to move away. These automatic devices are furthermore increasingly widely used in public areas, and in companies.
Ventricular fibrillation results in certain death if defibrillation is not performed immediately. In France, it kills approximately 40,000 people a year. Each minute that passes is considered to lower the chances of survival by approximately 10%, given that after five minutes survival is accompanied by irreversible serious neurological damage. However, it is known that the majority of sudden deaths for which an external defibrillator could be used occur at the victim's home. The automatic or semi-automatic defibrillators intended for use by non-professionals existing on the market are not very suitable for household use for several reasons, including in particular the fact that they are too costly and insufficiently ergonomic. It is thus desirable to have more specialized devices for this household use which are simpler, less expensive, and more user-friendly, without making any sacrifices in terms of the performances thereof.
The prior art contains numerous documents describing the control of a defibrillator by a remote qualified person. By way of example, the U.S. Pat. No. 6,405,083 (Philips) describes a defibrillator capable of transmitting an electrocardiogram to a remote call center via a wireless link. Based on this information, a competent person will decide whether to perform defibrillation and sends the decision to the user on-site. Similarly, the US patent application 2004/020473 (Grath) describes the remote control of a defibrillator of a known type by a remote computer, via a wireless link. The U.S. Pat. No. 7,672,720 (Heath) describes an emergency medical device comprising an automatic defibrillator and further therapeutic and/or diagnostic functions (respiratory support, electrocardiogram recorder) and which is capable of communicating with an external computer. The U.S. Pat. No. 7,162,306 (MedTronic) and U.S. Pat. No. 6,321,113 (SurVivaLink) describe computer networking of a standard external automatic defibrillator.
The U.S. Pat. No. 6,148,342 (Cardiac Science, Inc.) describes a defibrillator which can be carried permanently by a patient at risk. This ensures maximum safety, the device being immediately available if required, but is however very restrictive and reserved for patients having a maximum risk as an alternative to implantable subcutaneous defibrillators. The document US 2009/0240297 (Shavit) describes a defibrillator electrode with a built-in electrical power supply and remote control receiver which can be activated remotely by a cellular telephone.
The document WO 2007/140142 (Saketkhou) describes the idea of integrating a defibrillator function in a cellular telephone. In view of the low capacity of cellular telephone batteries, this seems unfeasible in the current state of the art.
The problem addressed by the present invention is that of providing a self-contained external cardiac defibrillator that is simple, compact, lightweight, inexpensive, easy to use by non-professionals and which is designed specially with a view to household use with the choice of “automatic” or “semi-automatic” use.